The Children's General Clinical Research Center at the University of Colorado Medical Center is a 6-bed facility designed to provide hospitalization with superior nursing and laboratory support for the investigation of disease in childhood. A significant part of the facility continues to operate in support of certain aspects of the organ transplantation program, including hepatic transplantation. Currently, an expanding bone marrow transplantation research program for leukemia, aplastic anemia and certain other diseases represents a major activity of this Center. The Center continues to be actively used in the investigation of rare inborn errors of metabolism, including glutaric aciduria and acrodermatitis enteropathica. Other new projects include the study of etiologic and pathologic mechanisms in allergic vasculitis and of the mechanisms of glomerular injury in sickle cell nephropathy. Pediatric surgical research projects include evaluation of hepatic porticoenterostomy in the treatment of biliary atresia and of portal diversion procedures for Type II hyperlipoproteinemia, and certain cases of glycogen storage disease. There is, in addition, an active outpatient effort, with 46 approved protocols, and the Core Laboratory continues its essential supportive role. Ambulatory research includes a major emphasis on nutritional research, especially trace element nutrition and hyperlipidemia states.